Goal c - Free a Singleton Property

Question

I have a singleton class that has mutableDictionary. I initialize the dictionary in my root viewController. later I would like to free the dictionary and free the memory. Although the hold count is 1, the release causes a failure:

- [CFDictionary release]: message sent to the freed instance

Is it possible to release the singleton property?

thank

Answer 1

First I repeat what has been said many times here: Do not call -retainCount!! This is an implementation detail.

See: StackOverflow | when to use saveCount for an excellent recount on why you are not using saveCount.

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Answer 2

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Answer 3

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Answer 4

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• If the dictionary stores the objects that you want to unlock in the event of a memory warning, perform a one-time observation UIApplicationDidReceiveMemoryWarningNotificationand delete all its objects there.

• If you really want your implementation to free the entire dictionary, I would override the synthesized getter and add singleton methods to interact with the dictionary as follows:

in MySingleton.m:

- (NSMutableDictionary *)myDictionary
{
    if (!_myDictionary) {
        _myDictionary = [[NSMutableDictionary alloc] init];
    }
    return _myDictionary;
}

- (void)setObject:(id)object inMyDictionaryForKey:(NSString *)key
{
    [self.myDictionary setObject:object forKey:key];
}

- (void)removeObjectInMyDictionaryForKey:(NSString *)key
{
    [self.myDictionary removeObjectForKey:key];
    if ([self.myDictionary count] == 0) {
        self.myDictionary = nil;
    }
}

- (void)removeAllObjectsFromMyDictionary
{
    self.myDictionary = nil;
}